What is Redis?
Redis is an advanced key-value cache and store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets, sorted sets, bitmaps and hyperloglogs.
TLDR
docker run --name redis bitnami/redis:latest
Docker Compose
version: '2'
services:
redis:
image: 'bitnami/redis:latest'
ports:
- '6379:6379'
Get this image
The recommended way to get the Bitnami Redis Docker Image is to pull the prebuilt image from the Docker Hub Registry.
docker pull bitnami/redis:latest
To use a specific version, you can pull a versioned tag. You can view the list of available versions in the Docker Hub Registry.
docker pull bitnami/redis:[TAG]
If you wish, you can also build the image yourself.
docker build -t bitnami/redis:latest https://github.com/bitnami/bitnami-docker-redis.git
Persisting your database
If you remove the container all your data and configurations will be lost, and the next time you run the image the data and configurations will be reinitialized. To avoid this loss of data, you should mount a volume that will persist even after the container is removed.
Note! If you have already started using your database, follow the steps on backing up and restoring to pull the data from your running container down to your host.
The image exposes a volume at /bitnami/redis
for the Redis data and configurations. For persistence you can mount a directory at this location from your host. If the mounted directory is empty, it will be initialized on the first run.
docker run -v /path/to/redis-persistence:/bitnami/redis bitnami/redis:latest
or using Docker Compose:
version: '2'
services:
redis:
image: 'bitnami/redis:latest'
ports:
- '6379:6379'
volumes:
- /path/to/redis-persistence:/bitnami/redis
Connecting to other containers
Using Docker container networking, a Redis server running inside a container can easily be accessed by your application containers.
Containers attached to the same network can communicate with each other using the container name as the hostname.
Using the Command Line
In this example, we will create a Redis client instance that will connect to the server instance that is running on the same docker network as the client.
Step 1: Create a network
$ docker network create app-tier --driver bridge
Step 2: Launch the Redis server instance
Use the --network app-tier
argument to the docker run
command to attach the Redis container to the app-tier
network.
$ docker run -d --name redis-server \
--network app-tier \
bitnami/redis:latest
Step 3: Launch your Redis client instance
Finally we create a new container instance to launch the Redis client and connect to the server created in the previous step:
$ docker run -it --rm \
--network app-tier \
bitnami/redis:latest redis-cli -h redis-server
Using Docker Compose
When not specified, Docker Compose automatically sets up a new network and attaches all deployed services to that network. However, we will explicitly define a new bridge
network named app-tier
. In this example we assume that you want to connect to the Redis server from your own custom application image which is identified in the following snippet by the service name myapp
.
version: '2'
networks:
app-tier:
driver: bridge
services:
redis:
image: 'bitnami/redis:latest'
networks:
- app-tier
myapp:
image: 'YOUR_APPLICATION_IMAGE'
networks:
- app-tier
IMPORTANT:
- Please update the YOUR_APPLICATION_IMAGE_ placeholder in the above snippet with your application image
- In your application container, use the hostname
redis
to connect to the Redis server
Launch the containers using:
$ docker-compose up -d
Configuration
Setting the server password on first run
Passing the REDIS_PASSWORD
environment variable when running the image for the first time will set the Redis server password to the value of REDIS_PASSWORD
.
docker run --name redis -e REDIS_PASSWORD=password123 bitnami/redis:latest
or using Docker Compose:
version: '2'
services:
redis:
image: 'bitnami/redis:latest'
ports:
- '6379:6379'
environment:
- REDIS_PASSWORD=password123
Setting up a replication
A replication cluster can easily be setup with the Bitnami Redis Docker Image using the following environment variables:
REDIS_REPLICATION_MODE
: The replication mode. Possible valuesmaster
/slave
. No defaults.REDIS_MASTER_HOST
: Hostname/IP of replication master (slave parameter). No defaults.REDIS_MASTER_PORT
: Server port of the replication master (slave parameter). Defaults to6379
.REDIS_MASTER_PASSWORD
: Password to authenticate with the master (slave parameter). No defaults.
In a replication cluster you can have one master and zero or more slaves. When replication is enabled the master node is in read-write mode, while the slaves are in read-only mode. For best performance its advisable to limit the reads to the slaves.
Step 1: Create the replication master
The first step is to start the Redis master.
docker run --name redis-master \
-e REDIS_REPLICATION_MODE=master \
-e REDIS_PASSWORD=masterpassword123 \
bitnami/redis:latest
In the above command the container is configured as the master
using the REDIS_REPLICATION_MODE
parameter. The REDIS_PASSWORD
parameter enables authentication on the Redis master.
Step 2: Create the replication slave
Next we start a Redis slave container.
docker run --name redis-slave \
--link redis-master:master \
-e REDIS_REPLICATION_MODE=slave \
-e REDIS_MASTER_HOST=master \
-e REDIS_MASTER_PORT=6379 \
-e REDIS_MASTER_PASSWORD=masterpassword123 \
-e REDIS_PASSWORD=password123 \
bitnami/redis:latest
In the above command the container is configured as a slave
using the REDIS_REPLICATION_MODE
parameter. The REDIS_MASTER_HOST
, REDIS_MASTER_PORT
and REDIS_MASTER_PASSWORD
parameters are used connect and authenticate with the Redis master. The REDIS_PASSWORD
parameter enables authentication on the Redis slave.
You now have a two node Redis master/slave replication cluster up and running which can be scaled by adding/removing slaves.
If the Redis master goes down you can reconfigure a slave to become a master using:
docker exec redis-slave redis-cli -a password123 SLAVEOF NO ONE
Note: The configuration of the other slaves in the cluster needs to be updated so that they are aware of the new master. In our example, this would involve restarting the other slaves with
--link redis-slave:master
.
With Docker Compose the master/slave replication can be setup using:
version: '2'
services:
redis-primary:
image: 'bitnami/redis:latest'
ports:
- '6379'
environment:
- REDIS_REPLICATION_MODE=master
- REDIS_PASSWORD=my_password
volumes:
- '/path/to/redis-persistence:/bitnami/redis'
redis-secondary:
image: 'bitnami/redis:latest'
ports:
- '6379'
depends_on:
- redis-primary
environment:
- REDIS_REPLICATION_MODE=slave
- REDIS_MASTER_HOST=redis-primary
- REDIS_MASTER_PORT=6379
- REDIS_MASTER_PASSWORD=my_password
- REDIS_PASSWORD=my_password
Scale the number of slaves using:
docker-compose scale redis-primary=1 redis-secondary=3
The above command scales up the number of slaves to 3
. You can scale down in the same way.
Note: You should not scale up/down the number of master nodes. Always have only one master node running.
Configuration file
The image looks for configuration in the conf/
directory of /bitnami/redis
. As as mentioned in Persisting your database you can mount a volume at this location and copy your own configurations in the conf/
directory. The default configuration will be copied to the conf/
directory if it's empty.
Step 1: Run the Redis image
Run the Redis image, mounting a directory from your host.
docker run --name redis -v /path/to/redis-persistence:/bitnami/redis bitnami/redis:latest
or using Docker Compose:
version: '2'
services:
redis:
image: 'bitnami/redis:latest'
ports:
- '6379:6379'
volumes:
- /path/to/redis-persistence:/bitnami/redis
Step 2: Edit the configuration
Edit the configuration on your host using your favorite editor.
vi /path/to/redis-persistence/conf/redis.conf
Step 3: Restart Redis
After changing the configuration, restart your Redis container for changes to take effect.
docker restart redis
or using Docker Compose:
docker-compose restart redis
Further Reading:
Logging
The Bitnami Redis Docker image sends the container logs to the stdout
. To view the logs:
docker logs redis
or using Docker Compose:
docker-compose logs redis
You can configure the containers logging driver using the --log-driver
option if you wish to consume the container logs differently. In the default configuration docker uses the json-file
driver.
Maintenance
Backing up your container
To backup your data, configuration and logs, follow these simple steps:
Step 1: Stop the currently running container
docker stop redis
or using Docker Compose:
docker-compose stop redis
Step 2: Run the backup command
We need to mount two volumes in a container we will use to create the backup: a directory on your host to store the backup in, and the volumes from the container we just stopped so we can access the data.
docker run --rm -v /path/to/redis-backups:/backups --volumes-from redis busybox \
cp -a /bitnami/redis:latest /backups/latest
or using Docker Compose:
docker run --rm -v /path/to/redis-backups:/backups --volumes-from `docker-compose ps -q redis` busybox \
cp -a /bitnami/redis:latest /backups/latest
Restoring a backup
Restoring a backup is as simple as mounting the backup as volumes in the container.
docker run -v /path/to/redis-backups/latest:/bitnami/redis bitnami/redis:latest
or using Docker Compose:
version: '2'
services:
redis:
image: 'bitnami/redis:latest'
ports:
- '6379:6379'
volumes:
- /path/to/redis-backups/latest:/bitnami/redis
Upgrade this image
Bitnami provides up-to-date versions of Redis, including security patches, soon after they are made upstream. We recommend that you follow these steps to upgrade your container.
Step 1: Get the updated image
docker pull bitnami/redis:latest
or if you're using Docker Compose, update the value of the image property to
bitnami/redis:latest
.
Step 2: Stop and backup the currently running container
Before continuing, you should backup your container's data, configuration and logs.
Follow the steps on creating a backup.
Step 3: Remove the currently running container
docker rm -v redis
or using Docker Compose:
docker-compose rm -v redis
Step 4: Run the new image
Re-create your container from the new image, restoring your backup if necessary.
docker run --name redis bitnami/redis:latest
or using Docker Compose:
docker-compose start redis
Notable Changes
3.2.0-r0
- All volumes have been merged at
/bitnami/redis
. Now you only need to mount a single volume at/bitnami/redis
for persistence. - The logs are always sent to the
stdout
and are no longer collected in the volume.
Contributing
We'd love for you to contribute to this container. You can request new features by creating an issue, or submit a pull request with your contribution.
Issues
If you encountered a problem running this container, you can file an issue. For us to provide better support, be sure to include the following information in your issue:
- Host OS and version
- Docker version (
docker version
) - Output of
docker info
- Version of this container (
echo $BITNAMI_IMAGE_VERSION
inside the container) - The command you used to run the container, and any relevant output you saw (masking any sensitive information)
License
Copyright (c) 2015-2016 Bitnami
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.